import React, { Component } from "react";

import {nanoid} from 'nanoid'
import "./index.css"

export default class Header extends Component {

  handleKeyUp = (event) => {
    const {keyCode, target} = event
    if (keyCode !== 13) return
    if (target.value.trim() === '') {
      alert ('输入不能为空')
      return
    }
    const todoObj = {id: nanoid(), name: target.value, done:false}
    this.props.addTodo (todoObj)
    target.value = ''
  }

  render() {
    return (
      <div className="todo-header">
        <input onKeyUp = {this.handleKeyUp} type="text" placeholder="请输入你的任务名称，按回车键确认" />
      </div>
    )
  }
}